Preparation and Microwave Absorbing Properties of an Electroless Ni‐Co Coating on Multiwall Carbon Nanotubes Using [Ag(NH3)2]+ as Activator

• DOI: 10.1155/2015/404698
• Publication Date: 2015-10-01T21:14:09Z
• Authors: Qiao-ling Li; Xiao-yong He; Yue-qing Zhang; Xiao-feng Yang
• Keywords: 02 engineering and technology; 0210 nano-technology

Ni‐Co‐coated carbon nanotubes (CNTs) composites with different molar ratios of Ni/Co were synthesized using [Ag(NH3)2]+ as activator and as reductant, thereby replacing the conventional noble metal Pd salt activator and Sn2+ reductant. Scanning electron microscopy, X‐ray diffraction, and X‐ray energy dispersive spectrometry analyses demonstrated that the CNTs were deposited with a dense, uniform Ni‐Co coating. The possible mechanism of the electroless method was studied, which indicates that pure Ag0 acted as a nucleation site for subsequent Ni‐Co‐P deposition. Network vector analyzer measurements indicated that the composite with only Ni coated had an absorbing value of −12.6 dB and the composite with a Ni/Co ratio of four had the maximum wave absorption (−15.6 dB) and the widest absorption bandwidth (800 MHz, RL < −10 dB), while the saturation magnetization (Ms) was 4.28 emu·g−1 and the coercive force (Hc) was 31.33 Oe.